The present inventions are related to systems and methods for writing data to a storage medium.
In conventional recording systems there is a tradeoff between the longevity of data stored to a storage medium and the writeability of the storage medium. Small grain size is required for high-density recording. Such small grain size renders the stored data more susceptible to thermal agitation resulting in destruction of the magnetization representing the stored data. In some cases, medium coercivity is increased to mitigate the aforementioned effect of thermal agitation, but such an increase in coercivity has not proven able to surpass values magnetizable by about two Tesla flux densities, a limit imposed by the saturation magnetization of the soft magnetic materials of which the write head is fabricated.
Use of heat-assisted magnetic recording addresses the writeability versus longevity dilemma by locally heating the storage medium during writing to near its Curie temperature allowing magnetization by existing write head designs relying on achievable flux densities. In some cases, the heating is done using a concentrated laser beam typically of 800 nm-1000 nm wavelength; beam concentration below the diffraction limit is typically achieved using near-field techniques based on plasmon resonance. Such an approach is more fully described in D. Weller et al., “Thermal Limits in Ultrahigh-Density magnetic Recording”, IEEE Trans. Magn., Vol. 35, No. 6, p. 4423, Nov. 1999. The entirety of the aforementioned reference is incorporated herein by reference for all purposes. While such an approach offers promise of improved data storage devices and systems, current control of the laser in relation to other write circuitry has been insufficient to yield commercially viable systems.
Hence, for at least the aforementioned reasons, there exists a need in the art for advanced systems and methods for control of the laser relative to other write circuitry.